Area Forecast Discussion
Issued by NWS Aberdeen, SD
Issued by NWS Aberdeen, SD
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350 FXUS63 KABR 241146 AAA AFDABR Area Forecast Discussion...UPDATED National Weather Service Aberdeen SD 646 AM CDT Fri May 24 2024 .KEY MESSAGES... - Showers and a few thunderstorms will persist for some areas today(30-70%) with rain chances diminishing southwest to northeast during the afternoon hours. - Cooler temperatures will be ushered in on strong west to northwest winds today. Peak gusts will reach 45-50 mph in portions of central and northeast South Dakota this morning through the afternoon where a Wind Advisory has been posted. - The unsettled weather pattern continues with chances of showers and thunderstorms Saturday night/Sunday (35-70% chance) and Monday 25-35% chance) before things dry out for much of the rest of the forecast. && .UPDATE... Issued at 634 AM CDT Fri May 24 2024 See below for an aviation forecast discussion for the 12Z TAFs. && .SHORT TERM /TODAY THROUGH SATURDAY AFTERNOON/... Issued at 424 AM CDT Fri May 24 2024 The main focus in this period will be the exiting precip chances today along with the increasing west to northwest winds that will set up as low pressure spirals and spins east to northeast out of the forecast area. Early this morning, we continue to see showers shift north- northeastward along and out ahead of a sfc cold front that is working through the James Valley. This precip has been mostly in the form of rain showers since the midnight hour, but a few weak storms will be possible across northeast SD and west central MN through the morning hours. We also expect another area of showers to curl into our western zones later this morning. Associated with the mid lvl low, this area of showers will shift west to east and then northeast with time during the daytime hours. A few weak storms will also be possible later this afternoon across our northeast zones as the mid level disturbance rotates into eastern ND. Cold air advection on the backside of this system will lead to a rather cool day today. 850mb temperatures drop to around zero across at least the northern half of the forecast area by midday through the late afternoon. Highs will likely only warm into the low to mid 60s which is close to 10 degrees below normal in some areas for this time of year. The combination of the cold air advection and a 6-8mb pressure bubble shifting west to east across the forecast area this morning through the afternoon will lead to an increasing west to northwest wind from west to east. 1/2km winds are progged to increase to around 40kts West River by early-mid morning and then shift northeast toward the Leola Hills toward midday and afternoon. NBM probabilities for wind gusts reaching or exceeding 45mph are in the 50-80 percent range across central SD. BUFKIT profiles indicate 40- 45kts mixing down across central and parts of northeast SD. Based on these factors, have issued a Wind Advisory starting first across our West River zones early this morning. East river zones up to but just west of the James Valley get in on these advisory level winds closer to midday. By late this afternoon and early evening, we should begin to see improving conditions as winds gradually diminish. A weak sfc ridge passes across the area tonight. Clear to partly cloudy skies and cool temperatures will settle in overnight with readings bottoming out in the upper 30s north to the low to mid 40s elsewhere. This high will shift quickly east on Saturday as a warm front nudges into SD associated with the next lee of the Rockies low pressure that`s progged to develop. Mainly dry conditions with warm advection returning will boost temps back closer to normal with low to mid 70s for highs. By late in the period, we will have to keep an eye on trends for the potential for storms to return to parts central SD. && .LONG TERM /SATURDAY EVENING THROUGH THURSDAY/... Issued at 424 AM CDT Fri May 24 2024 As the longwave trof over the western CONUS, at the start of the period, gradually gets replaced by an upper level ridge, the remaining pieces of shortwave energy will be redirected eastward across the nation`s mid-section (clusters analysis). Two of these pieces of shortwave energy are progged to move across South Dakota/Nebraska Saturday night through Monday before the upper level ridging kicks in (NBM PoPs of 20-55% through said period). Dry conditions appear to be in the offing for Monday night through Thursday while this upper level ridge moves east and longwave troffing ensues behind it over the western CONUS. With height falls noted Thursday and Friday, and a surface pressure pattern shift to return flow southerly winds, precipitation chances pick back up (20- 45% NBM PoPs) by Thursday night into Friday. After Monday, near normal temperatures are anticipated (NAEFS/ECMWF S.A. Table 850hpa thermal anomalies roughly between -0.5 and +0.5 of "climatology"), which means highs generally in the 70s and lows in the upper 40s to low 50s. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 634 AM CDT Fri May 24 2024 Terminals KABR,KATY,KPIR,KMBG Will continue with off and on periods of -RA at KMBG, KABR and KATY today, as the upper level low pressure circulation between Bismarck and Mobridge slowly spins away from the region. Sub-VFR cigs are in play across the western Dakotas this morning, and will impact the KPIR and KMBG terminals through ~mid-day before conditions improve into VFR flying weather this afternoon. Good VFR will then persist at all four terminals through the rest of the TAF valid period. What won`t improve quite so quickly is the strong northwest winds of 20 to 30 knots with gusts of 40 to 45 knots. Theses winds will stick around until mid/late afternoon before gradually diminishing. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...Wind Advisory until 6 PM CDT /5 PM MDT/ this evening for SDZ003- 015-033-045-048. Wind Advisory from noon today to 8 PM CDT this evening for SDZ004-005-009-010-016-017-034>037-051. MN...None. && $$ UPDATE...Dorn SHORT TERM...Vipond LONG TERM...Dorn AVIATION...Dorn